Most portable sample detectors only identify one analyte for a given singular device. These analyte detections often rely upon the users ability to select the correct device for a specific analyte. During sampling, users may not be fully knowledgeable of all of the analytes that can possibly be present in the environment. This situation can lead to longer detection times and prolonged durations in a hazardous environment, which may cause severe injuries or death. Additionally, low volatility and/or solid phase analytes (i.e. ammonium nitrate, perchlorate salts, urea, and urea nitrate) do not produce enough vaporous mass due to their inherently low volatilities and, thus, cannot be detected via traditional selective vapor phase sampling means (i.e., ICAM and JCAD).
Given this, a Colorimetric Homemade Explosive Detector (“CHED”) or colorimetric reconnaissance Explosive Squad Screening (“CRESS”) kit has been developed for this purpose. It is a collection/concentration sampler and detector of liquid or solid phase analytes from diverse environmental matrixes, specifically explosive compounds (or their precursors). Briefly, one uses the sampler component of the CRESS kit to pick up a solid or liquid sample from a surface, which is then folded over the detector component. The CRESS kit further includes colorimetric reagent-containing ampoules located above the sampler component. The user breaks the ampoules to allow the reagent to dissolve the sample and to be absorbed into a swatch of absorbent paper within the detector component. The resultant colors are developed on the paper and are visible through transparent windows, each of which contains an integrated color chart to indicate positive and negative colors.
However, in order to assess the degree of hazard from an unknown substance collected from the environment, users of the CRESS kit need to be trained to interpret the combination of colors from the different visualization windows in CRESS. It is unsafe to use the real hazardous chemicals to produce color changes for training purposes. Therefore, there remains a need for harmless simulated explosive compositions, such that they require minimal or no manipulations to produce the color response of their hazardous counterparts within the CRESS kit.